xTC: An efficient treatment of three-body interactions in transcorrelated methods

TL;DR

The paper introduces xTC, an efficient approximation method for three-body interactions in transcorrelated quantum chemistry, achieving near-chemical accuracy with reduced computational scaling.

Contribution

It presents a novel implementation of xTC that simplifies three-body operator inclusion, significantly reducing computational complexity in transcorrelated methods.

Findings

Achieved near-chemical accuracy on the HEAT benchmark set.

Reduced the scaling of three-body calculations to O(N^5).

Demonstrated broad applicability with various correlation methods.

Abstract

An efficient implementation for approximate inclusion of the three-body operator arising in transcorrelated methods via exclusion of explicit three-body components (xTC) is presented and tested against results in the "HEAT" benchmark set [A. Tajti et al., J. Chem. Phys. 121, 11599 (2004)]. Using relatively modest basis sets and computationally simple methods, total, atomization, and formation energies within near-chemical accuracy from HEAT results were obtained. The xTC ansatz reduces the nominal scaling of the three-body part of transcorrelation by two orders of magnitude to O(N^5) and can readily be used with almost any quantum chemical correlation method.